Test tube rack

ABSTRACT

A test tube rack expressly constructed for expedient chemistry analysis in industrial laboratories is provided with means to hold a plurality of test tubes and to seal them after filling so that the contents may be mixed adequately. The rack includes a bottom shelf recessed to receive the lower ends of the test tubes and a cover with a locking mechanism especially designed to provide a quick connect and disconnect operation. The cover is lined with a resilient sheet impervious to chemical compounds so as to provide a hermetic seal to the test tubes, the resiliency allowing for height differential between the ends of different size tubes.

[4 Mar. 18, 1975 TEST TUBE RACK [75] Inventor: Alcide Leblanc, Montreal,Quebec,

Canada [73] Assignee: Institut de Bio-Endrocrinologie, lnc., Montreal,Canada [22] Filed: Mar. 5, 1974 [211 App]. No.: 448,360

Primary E.\-aminer-R. E. Serwin Attorney, Agent, or Firm-Cushman, Darby& Cushman [57] ABSTRACT A test tube rack expressly constructed forexpedient chemistry analysis in industrial laboratories is provided withmeans to hold a plurality of test tubes and to seal them after fillingso that the contents may be mixed adequately. The rack includes a bottomshelf recessed to receive the lower ends of the test tubes and a coverwith a locking mechanism especially designed to provide a quick connectand disconnect operation. The cover is lined with a resilient sheetimpervious to chemical compounds so as to provide a hermetic seal to thetest tubes, the resiliency allowing for height differential between theends of different size tubes.

12 Claims, 3 Drawing Figures PATENTED 81975 0000 Q o o 0 TEST TUBE RACKFIELD OF THE INVENTION The present invention relates to a rack forretaining multiple spaced test tubes. More particularly, the inventionpertains to an improved locking device for placing the cover of the rackin sealing position over the open ends of the test tubes and forproviding quick connect and disconnect operation.

BACKGROUND OF THE INVENTION In industrial laboratories, test tubes maybe used, for example, to receive different samples of blood. These tubesare closed with glass or rubber stoppers to allow a mixing of thecontents therein. Obviously, the opening and closing procedures involvedwith these tubes are laborious and time-consuming and most stopperscarry plenty of practical difficulties. The price of these tubes isespecially high if all the components of a tube are made of glass. Inthe cases where cork or rubber caps are used, the price may be reducedbut there are plenty of leaks and often rubber is attacked by some ofthe chemical solvents. There is also a danger of contamination with anykind of stoppering because of a possible mix-up with the respectivestoppers of a series of tubes.

Another disadvantage of present known methods is a lack of uniformity ofresults. Since all mixing operations are individually carried out and itis practically impossible to have a series of identical operations.

STATEMENT OF THE INVENTION It is an object of the present invention toprovide a test tube rack which is constructed for expedient chemistryanalysis in industrial laboratories and which overcomes the abovementioned disadvantages by saving valuable time and labor and ensuringnoncontamination of the contents in the test tubes.

The test tube rack made in accordance with the present inventionconsists of a bottom shelf and a spaced parallel support arranged toreceive a series of test tubes disposed in longitudinal and lateralrows. A re-. movable cover is provided for simultaneously cap the testtubes. The lower face of the cover includes a liner made of a resilientresistant sheet impervious to chemical compounds so as to provide ahermetic seal for the test tubes. The rack also includes an improvedlocking mechanism which enables a quick connect and disconnect operationfor capping and decapping the test tubes.

With a rack made in accordance with the present invention, the height ofthe tubes positioned therein is no longer critical since any differencein their height is taken up by the resiliency in the liner. Foradditional resiliency, small rubber cushions may be placed in concavedepressions provided in the bottom shelf and serving as seats for thelower part of the test tubes.

Also, all mixing and agitating operations are now carried outsimultaneously; this confers homogeneity of results. It is well knownthat all batches include blanks and any known or unknown values are thesame for the testing of all tubes of one rack.

The novel locking mechanism of the present invention consists ofsecuring means which are mounted to the bottom shelf of the rack andhave a portion protruding the cover; actuator means are disposed abovethe cover have a lower portion slidably extending through the cover;lever means are pivotally attached at one end thereof to the upperportion of the actuator means. The other end of the lever means isprovided with engagement means for engaging the protruding portion ofthe securing means. Pivot means are provided on the lever means and arein contact engagement with the upper face of the cover. On downwardmovement of the actuator means, the lever means move outwardly to theprotruding portion of the securing means where the engagement meansengage the said protruding portion to provide a tight sealing engagementbetween the liner and the tubes.

BRIEF DESCRIPTION OF THE DRAWINGS Other objects, purposes andcharacteristic features of the present invention will be in part obviousfrom the accompanying drawings and in part pointed out as'thedescription of the invention progresses. In describing the invention indetail, reference will be made to the accompanying drawings, in whichlike reference characters designate corresponding parts throughout theseveral views, and in which:

FIG. 1 is an elevational view of a test tube rack made in accordancewith the present invention;

FIG. 2 is a cross-sectional view taken along lines 22 of FIG. 1; and

FIG. 3 is an elevational view showing part of the rack of the presentinvention and illustrating the locking mechanism in the opened position.

DESCRIPTION OF PREFERRED EMBODIMENT Referring to FIG. 1, there isillustrated a rack having a bottom shelf 12 of rectangular flat shapeand having extending vertically at each corner thereof a series ofvertical supports 14 (two of which are shown). Spaced parallel and abovethe bottom shelf 12 is an intermediate support 16 which is fixedlyattached at its corners to the supports 14 by appropriate securingmeans, such aspairs of nuts 18 and 19 threadedly mounted on the supports14.

The bottom shelf 12 is provided with a series of circular concavedepressions 20 which are adapted to receive the lower part of a seriesof open end test tubes 22 arranged in longitudinal and lateral rows. Theintermediate support 16 is provided with a series of openings 26 whichare in vertical registry with the lower depressions ofthe bottom shelf12; support 16 ensures the vertical support of the test tubes 22 in therack.

A cover 28 of rectangular shape is adapted to be laid over the open endsof the test tubes 22. The cover includes a top plate 29 and a liner 30secured to the lower face of the plate 29; the liner is made of aresilient resistant sheet of material impervious to chemical compoundsand its function will be described hereinbelow.

An important characteristic of the present invention is a novel lockingmechanism for locking the cover 28 in a sealing engagement over the openends of the test tubes. This locking mechanism consists of a pair ofsecuring means in the form of a vertical plate member 32 which has itslower end fixed to the bottom shelf 12 and which has, as its oppositeupper end, a portion 34 that protrudes the top plate 29 and the liner30. Plate 32 may be adjusted vertically relative to the bottom shelf bymeans of a screw 46 threadedly engaged thereto, the head 48 of the screwbeing accessible beneath the bottom shelf. When the plate is adjusted toraise it relative to shelf 16, a spring 50 disposed between the plateand the shelf upwardly urges the plate. The novel locking mechanismfurther includes an actuator means 36 slidably mounted to the cover 28and a pair of lever means 38, each having one end 40 pivotally mountedto an upper part of actuator means 36 and the other end 42 equipped withengagement means 44 for engaging the protruding portion 34 of thesecuring plate 32.

The actuator means 36 consists of a flat handle 52 and of an elongatedplate 54 extending through the plate 29 and the liner 30. A pin 56extends transversely of the plate 54 at its lower edge to engage liner30 and to subsequently lift the cover plate 28 when the actuator meansare pulled upward. Two curved slots 58 on the upper part of plate 54receive the cross pins 60 which extend transversely through thefork-shaped upper ends 40 of the levers 38.

The opposite end 42 of the lever means is also forkshaped and receivestransversely thereof a pin 44. A similar transverse pin 62 extends loweron the lever means and supports a roller 64 which is adapted to slide onthe upper face of the top plate 29 of the cover.

The protruding portion 34 of the securing plate 32 has a mouth-shapedopening sufficiently large to receive the engagement means 44 and theroller 64 of end 42 of the lever means.

Appropriate slots are provided in the intermediate support 16, plate 29and liner 30 to allow the passage of plates 32 and 54 therethrough; asseen in FIG. 2, slots 66 are provided to allow passage of plates 32while slot 68 allows passage of the actuator plate 54. Similar slots arefound on cover 28. Slot 68 further includes two opposite recesses 70 and72 to allow passage of the cross-pin 56 of plate 54; however, similarrecesses are not found on cover 28 since this pin 56 serves to engagethe cover as the latter is raised.

OPERATION OF THE EMBODIMENT Referring first to FIG. 3, the lockingmechanism is shown in a free position, that is when the cover is raisedor as the actuator means begins its downward actuation. In thisposition, the liner 30 lays over the open ends of the test tubes. As theactuator begins its downward travel, ends 42 of the lever means moveoutwardly toward the mouth-shaped openings 44 of the upper portions 34of the securing means 32. Pins 60 are at their lowest point in theirrespective slots 68; the slots allow easy passage of the lever means 38between the actuator plate 54 and the protruding portion 34 of thesecuring means. In a horizontal position, the levers would not clear theuppermost and inmost extremity of portions 34. As-the engagement means44 contact the inside edge of opening 45, pins 60 roll up the slots 58at their uppermost point. There, the actuator is held suspended.

To lock the cover plate in sealing engagement with the upper ends of thetest tubes, actuator 52 is further pushed downward in forcing mannersince pins 44 are already in contact with portion 34. There results apivot movement of the lever 38 about pin 62 which continues to furthermove outwardly and enter in opening 45. There, the locking mechanism isas that shown in FIG. 1 where the ends 42 are entirely received in themouthshaped opening 45 and where the pins 60 and 62 are substantially ina horizontal plane. Although not illustrated in the drawings, the planethat includes pins 62 and 44 is slightly offset toward the actuatormeans with respect to a vertical plane that includes pin 62. With thisarrangement, a force must be exerted on the actuator 52 to allow pin 44to rotate back in this vertical plane before being retracted from themouth-shaped opening 45.

With this arrangement, a satisfactory sealing engagement is obtainedbetween the liner 30 and the upper ends of the test tubes. When forcingthe cover plate on the test tubes, the resiliency in liner 30 takes upany height differential in the various test tubes of the rack. Toenhance this resiliency action, rubber rings (not shown) may bepositioned in the circular depressions 20 of the bottom shelf 12.

Although the invention has been described with respect to one specificform, it is evident that it may be modified and refined in various ways.For example, an indicator could be provided to the under surface of thebottom shelf 12 to indicate the degree of variation given to the screw46. It is therefore wished to have it understood that the presentinvention is not limited in interpretation except by the terms of thefollowing claims.

What I claim is:

l. A locking mechanism for locking a removable cover over a plurality ofopen ended tubes of a test tube rack, the cover including a resilientliner on the lower face thereof, comprising, in combination: verticalsecuring means having one end mounted to a bottom wall of said rack andhaving at the opposite end thereof a portion protruding said cover;actuator means having an upper portion disposed above said cover and alower portion slidably mounted through said cover; lever means pivotallyattached to one end thereof to the upper portion of said actuator means,the other end thereof defining engagement means for engaging saidprotruding portion of said securing means; pivot means on said levermeans in contacting engagement with the upper face of said cover, andbeing slidable thereon whereby, upon downward movement of said actuatormeans, said lever means are moved to said protruding portion of saidsecuring means and said engagement means tightly secure said protrudingportion to provide a sealing engagement between the liner and the tubes,the resiliency in said liner allowing for height differential betweenthe ends of the tubes.

2. A locking mechanism as defined in claim 1, said actuator means beingcentrally located on said cover and including a pair of said lever meansin securing engagement with a pair of said securing means symmetricallydisposed on each side of said actuator means.

3. A locking mechanism as defined in claim 1, further comprising meansmounted on said bottom wall of said rack for adjusting the relativeposition of said securing wherein said pivot means include a pinextending transversely of said lever means and a roller mounted on saidpin.

7. A locking mechanism as defined in claim 5, wherein said actuatormeans include at least one slot to receive therein the end of said levermeans which is pivotally attached thereto, said slot providing easyaccess of the other end of said lever means to said mouthshaped openingof said protruding portion of said securing means.

8. A locking mechanism as defined in claim 1, wherein the pivot axis ofsaid pivot means and the pivot axis of said end of said lever meanspivotally attached to said actuator means are in substantiallyhorizontal plane when said lever means are in a locking engagement withsaid protruding portion; said engagement of said lever means including apin extending transversely and horizontally in said lever means, thepivot axis of said pin being slightly offset with respect to a verticalplane passing through said pivot axis of said pivot means, the offsetbeing an inclination toward said actuator means.

9. A test tube rack comprising, in combination: a bottom shelf having aseries of depressions adapted to receive therein the lower end of testtubes; a horizontal tube support extending above from said bottom shelfand having a series of openings to receive therethrough the test tubes;vertical support means attached to said bottom shelf for supporting saidhorizontal support; a removable cover adapted to be in coveringarrangement over the open ends of the test tubes; a resilient linerfixed to the lower face of said cover and adapted to contact the openends of the test tubes; vertical securing means having one end fixed tosaid bottom shelf and having at the opposite thereof a portionprotruding said cover; cover actuator means having an upper portiondisposed above said cover and a lower portion slidably mounted throughsaid cover; lever means pivotally attached at one end thereof to theupper portion of said actuator means, the other end thereof definingengagement means for engaging said protruding portion of said securingmeans; pivot means on said lever means in contacting engagement withthe-upper face of said cover and being slidable thereon whereby, upondownward movement of said actuator means, said lever means are moved tosaid protruding portion of said securing means and said engagement meanstightly secure said protruding portion to provide a sealing engagementbetween the liner and the tubes, the resiliency in said liner allowingfor height differential between the ends of the tubes.

10. A test tube rack as defined in claim 9, further comprising resilientmeans in said depressions in said bottom shelf to provide resiliency atthe opposite end of the tubes when engaged between the liner and thebottom shelf.

11. A test tube rack as defined in claim 9, wherein said depressionsinclude orifices therein for discharging waste contents collected insaid depressions.

12. A test tube rack as defined in claim 9, wherein means are providedon the bottom shelf for adjusting the vertical height of said securingmeans relative'to said cover; means being provided beneath said bottomshelf for indicating the adjustment made on said securing means.

1. A LOCKING MECHANISM FOR LOCKING A REMOVABLE COVER OVER A PLURALITY OFOPEN ENDED TUBES OF A TEST TUBE RACK, THE COVER INCLUDING A RESILIENTLINER ON THE LOWER FACE THEREOF, COMPRISING, IN COMBINATION:VERTICALSECURING MEANS HAVING ONE END MOUNTED TO A BOTTOM WALL OF SAID RACK ANDHAVING AT THE OPPOSITE END THEREOF A PORTION PROTRUDING SAID COVER;ACTUATOR MEANS HAVING AN UPPER PORITION DISPOSED ABOVE SAID COVER AND ALOWER PORTION SLIDABLY MOUNTED THROUGH SAID COVER; LEVER MEANS PIVOTALLYATTACHED TO ONE END THEREOF TO THE UPPER PORTION OF SAID ACTUATOR MEANS,THE OTHER END THEREOF DEFINING ENGAGEMENT MEANS FOR ENGAGING SAIDPROTRUDING PORTION OF SAID SECURING MEANS; PIVOT MEANS ON SAID LEVERMEANS IN CONTACTING ENGAGEMENT WITH THE UPPER FACE OF SAID COVER, ANDBEING SLIDABLE THEREON WHEREBY, UPON DOWNWARD MOVEMENT OF SAID ACTUATORMEANS, SAID LEVER MEANS ARE MOVED TO SAID PROTRUDING PORTION OF SAIDSECURING MEANS AND SAID ENGAGEMENT MEANS TIGHTLY SECURE SAID PROTRUDINGPORTION TO PROVIDE A SEALING ENGAGEMENT BETWEEN THE LINER AND THE TUBES,THE RESILIENCY IN SAID LINER ALLOWING FOR HEIGHT DIFFERENTIAL BETWEENTHE ENDS OF THE TUBES.
 2. A locking mechanism as defined in claim 1,said actuator means being centrally located on said cover and includinga pair of said lever means in securing engagement with a pair of saidsecuring means symmetrically disposed on each side of said actuatormeans.
 3. A locking mechanism as defined in claim 1, further comprisingmeans mounted on said bottom wall of said rack for adjusting therelative position of said securing means with respect to said cover. 4.A locking mechanism as defined in claim 3, further comprising springmeans disposed between said bottom wall of said rack and said securingmeans for upwardly urging said securing means when adjusted.
 5. Alocking mechanism as defined in claim 1, wherein said protruding portionof said securing means above said cover includes a mouth-shaped openingsufficiently large to receive said engagement means and said pivot meanstherein.
 6. A locking mechanism as defined in claim 5, wherein saidpivot means include a pin extending transversely of said lever means anda roller mounted on said pin.
 7. A locking mechanism as defined in claim5, wherein said actuator means include at least one slot to receivetherein the end of said lever means which is pivotally attached thereto,said slot providing easy access of the other end of said lever means tosaid mouth-shaped opening of said protruding portion of said securingmeans.
 8. A locking mechanism as defined in claim 1, wherein the pivotaxis of said pivot means and the pivot axis of said end of said levermeans pivotally attached to said actuator means are in substantiallyhorizontal plane when said lever means are in a locking engagement withsaid protruding portion; said engagement of said lever means including apin extending transversely and horizontally in said lever means, thepivot axis of said pin being slightly offset with respect to a verticalplane passing through said pivot axis of said pivot means, the offsetbeing an inclination toward said actuator means.
 9. A test tube rackcomprising, in combination: a bottom shelf having a series ofdepressions adapted to receive therein the lower end of test tubes; ahorizontal tube support extending above from said bottom shelf andhaving a series of openings to receive therethrough the test tubes;vertical support means attached to said bottom shelf for supporting saidhorizontal support; a removable cover adapted to be in coveringarrangement over the open ends of the test tubes; a resilient linerfixed to the lower face of said cover and adapted to contact the openends of the test tubes; vertical securing means having one end fixed tosaid bottom shelf and having at the opposite thereof a portioNprotruding said cover; cover actuator means having an upper portiondisposed above said cover and a lower portion slidably mounted throughsaid cover; lever means pivotally attached at one end thereof to theupper portion of said actuator means, the other end thereof definingengagement means for engaging said protruding portion of said securingmeans; pivot means on said lever means in contacting engagement with theupper face of said cover and being slidable thereon whereby, upondownward movement of said actuator means, said lever means are moved tosaid protruding portion of said securing means and said engagement meanstightly secure said protruding portion to provide a sealing engagementbetween the liner and the tubes, the resiliency in said liner allowingfor height differential between the ends of the tubes.
 10. A test tuberack as defined in claim 9, further comprising resilient means in saiddepressions in said bottom shelf to provide resiliency at the oppositeend of the tubes when engaged between the liner and the bottom shelf.11. A test tube rack as defined in claim 9, wherein said depressionsinclude orifices therein for discharging waste contents collected insaid depressions.
 12. A test tube rack as defined in claim 9, whereinmeans are provided on the bottom shelf for adjusting the vertical heightof said securing means relative to said cover; means being providedbeneath said bottom shelf for indicating the adjustment made on saidsecuring means.